Day1-Ludwig Liang-2011 GCG STG Tech Coverage Model 20110425

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A_review_of_advanced_and_practical_lithium_battery_materials

A review of advanced and practical lithium battery materialsRotem Marom,*S.Francis Amalraj,Nicole Leifer,David Jacob and Doron AurbachReceived 3rd December 2010,Accepted 31st January 2011DOI:10.1039/c0jm04225kPresented herein is a discussion of the forefront in research and development of advanced electrode materials and electrolyte solutions for the next generation of lithium ion batteries.The main challenge of the ﬁeld today is in meeting the demands necessary to make the electric vehicle fully commercially viable.This requires high energy and power densities with no compromise in safety.Three families of advanced cathode materials (the limiting factor for energy density in the Li battery systems)are discussed in detail:LiMn 1.5Ni 0.5O 4high voltage spinel compounds,Li 2MnO 3–LiMO 2high capacity composite layered compounds,and LiMPO 4,where M ¼Fe,Mn.Graphite,Si,Li x TO y ,and MO (conversion reactions)are discussed as anode materials.The electrolyte is a key component that determines the ability to use high voltage cathodes and low voltage anodes in the same system.Electrode–solution interactions and passivation phenomena on both electrodes in Li-ion batteries also play signiﬁcant roles in determining stability,cycle life and safety features.This presentation is aimed at providing an overall picture of the road map necessary for the future development of advanced high energy density Li-ion batteries for EV applications.IntroductionOne of the greatest challenges of modern society is to stabilize a consistent energy supply that will meet our growing energy demands.A consideration of the facts at hand related to the energy sources on earth reveals that we are not encountering an energy crisis related to a shortage in total resources.For instancethe earth’s crust contains enough coal for the production of electricity for hundreds of years.1However the continued unbridled usage of this resource as it is currently employed may potentially bring about catastrophic climatological effects.As far as the availability of crude oil,however,it in fact appears that we are already beyond ‘peak’production.2As a result,increasing oil shortages in the near future seem inevitable.Therefore it is of critical importance to considerably decrease our use of oil for propulsion by developing effective electric vehicles (EVs).EV applications require high energy density energy storage devices that can enable a reasonable driving range betweenDepartment of Chemistry,Bar-Ilan University,Ramat-Gan,52900,Israel;Web:http://www.ch.biu.ac.il/people/aurbach.E-mail:rotem.marom@live.biu.ac.il;aurbach@mail.biu.ac.ilRotem MaromRotem Marom received her BS degree in organic chemistry (2005)and MS degree in poly-mer chemistry (2007)from Bar-Ilan University,Ramat Gan,Israel.She started a PhD in electrochemistry under the supervision of Prof.D.Aurbach in 2010.She is currently con-ducting research on a variety of lithium ion battery materials for electric vehicles,with a focus on electrolyte solutions,salts andadditives.S :Francis AmalrajFrancis Amalraj hails from Tamil Nadu,India.He received his MSc in Applied Chemistry from Anna University.He then carried out his doctoral studies at National Chemical Laboratory,Pune and obtained his PhD in Chemistry from Pune University (2008).He is currently a postdoctoral fellow in Prof.Doron Aurbach’s group at Bar-Ilan University,Israel.His current research interest focuses on the synthesis,electrochemical and transport properties of high ener-getic electrode materials for energy conversion and storage systems.Dynamic Article Links CJournal ofMaterials ChemistryCite this:DOI:10.1039/c0jm04225k /materialsFEATURE ARTICLED o w n l o a d e d b y B e i j i n g U n i v e r s i t y o f C h e m i c a l T e c h n o l o g y o n 24 F e b r u a r y 2011P u b l i s h e d o n 23 F e b r u a r y 2011 o n h t t p ://p u b s .r s c .o r g | d o i :10.1039/C 0J M 04225KView Onlinecharges and maintain acceptable speeds.3Other important requirements are high power density and acceptable safety features.The energy storage ﬁeld faces a second critical chal-lenge:namely,the development of rechargeable systems for load leveling applications (e.g.storing solar and wind energy,and reducing the massive wasted electricity from conventional fossil fuel combustion plants).4Here the main requirements are a very prolonged cycle life,components (i.e.,relevant elements)abun-dant in high quantities in the earth’s crust,and environmentally friendly systems.Since it is not clear whether Li-ion battery technology can contribute signiﬁcantly to this application,battery-centered solutions for this application are not discussedherein.In fact,even for electrical propulsion,the non-petroleum power source with the highest energy density is the H 2/O 2fuel cell (FC).5However,despite impressive developments in recent years in the ﬁeld,there are intrinsic problems related to electrocatalysis in the FCs and the storage of hydrogen 6that will need many years of R&D to solve.Hence,for the foreseeable future,rechargeable batteries appear to be the most practically viable power source for EVs.Among the available battery technologies to date,only Li-ion batteries may possess the power and energy densities necessary for EV applications.The commonly used Li-ion batteries that power almost all portable electronic equipment today are comprised of a graphite anode and a LiCoO 2cathode (3.6V system)and can reach a practical energy density of 150W h kg À1in single cells.This battery technology is not very useful for EV application due to its limited cycle life (especially at elevated temperatures)and prob-lematic safety features (especially for large,multi-cell modules).7While there are ongoing developments in the hybrid EV ﬁeld,including practical ones in which only part of the propulsion of the car is driven by an electrical motor and batteries,8the main goal of the battery community is to be able to develop full EV applications.This necessitates the development of Li-ion batteries with much higher energy densities compared to the practical state-of-the-art.The biggest challenge is that Li-ion batteries are complicated devices whose components never reach thermodynamic stability.The surface chemistry that occurs within these systems is very complicated,as described brieﬂy below,and continues to be the main factor that determines their performance.9Nicole Leifer Nicole Leifer received a BS degree in chemistry from MIT in 1998.After teaching high school chemistry and physics for several years at Stuyvesant High School in New York City,she began work towards her PhD in solid state physics from the City University of New York Grad-uate Center.Her research con-sisted primarily of employing solid state NMR in the study of lithium ion electrode materialsand electrode surfacephenomena with Prof.Green-baum at Hunter College andProf.Grey at Stony Brook University.After completing her PhD she joined Prof.Doron Aurbach for a postdoctorate at Bar-Ilan University to continue work in lithium ion battery research.There she continues her work in using NMR to study lithium materials in addition to new forays into carbon materials’research for super-capacitor applications with a focus on enhancement of electro-chemical performance through the incorporation of carbonnanotubes.David Jacob David Jacob earned a BSc from Amravati University in 1998,an MSc from Pune University in 2000,and completed his PhD at Bar-Ilan University in 2007under the tutelage of Professor Aharon Gedanken.As part of his PhD research,he developed novel methods of synthesizing metal ﬂuoride nano-material structures in ionic liquids.Upon ﬁnishing his PhD he joined Prof.Doron Aurbach’s lithium ionbattery group at Bar-Ilan in2007as a post-doctorate and during that time developed newformulations of electrolyte solutions for Li-ion batteries.He has a great interest in nanotechnology and as of 2011,has become the CEO of IsraZion Ltd.,a company dedicated to the manufacturing of novelnano-materials.Doron Aurbach Dr Doron Aurbach is a full Professor in the Department of Chemistry at Bar-Ilan Univer-sity (BIU)in Ramat Gan,Israel and a senate member at BIU since 1996.He chaired the chemistry department there during the years 2001–2005.He is also the chairman of the Israeli Labs Accreditation Authority.He founded the elec-trochemistry group at BIU at the end of 1985.His groupconducts research in thefollowing ﬁelds:Li ion batteries for electric vehicles and for otherportable uses (new cathodes,anodes,electrolyte solutions,elec-trodes–solution interactions,practical systems),rechargeable magnesium batteries,electronically conducting polymers,super-capacitors,engineering of new carbonaceous materials,develop-ment of devices for storage and conversion of sustainable energy (solar,wind)sensors and water desalination.The group currently collaborates with several prominent research groups in Europe and the US and with several commercial companies in Israel and abroad.He is also a fellow of the ECS and ISE as well as an associate editor of Electrochemical and Solid State Letters and the Journal of Solid State Electrochemistry.Prof.Aurbach has more than 350journals publications.D o w n l o a d e d b y B e i j i n g U n i v e r s i t y o f C h e m i c a l T e c h n o l o g y o n 24 F e b r u a r y 2011P u b l i s h e d o n 23 F e b r u a r y 2011 o n h t t p ://p u b s .r s c .o r g | d o i :10.1039/C 0J M 04225KAll electrodes,excluding 1.5V systems such as LiTiO x anodes,are surface-ﬁlm controlled (SFC)systems.At the anode side,all conventional electrolyte systems can be reduced in the presence of Li ions below 1.5V,thus forming insoluble Li-ion salts that comprise a passivating surface layer of particles referred to as the solid electrolyte interphase (SEI).10The cathode side is less trivial.Alkyl carbonates can be oxidized at potentials below 4V.11These reactions are inhibited on the passivated aluminium current collectors (Al CC)and on the composite cathodes.There is a rich surface chemistry on the cathode surface as well.In their lithiated state,nucleophilic oxygen anions in the surface layer of the cathode particles attack electrophilic RO(CO)OR solvents,forming different combinations of surface components (e.g.ROCO 2Li,ROCO 2M,ROLi,ROM etc.)depending on the electrolytes used.12The polymerization of solvent molecules such as EC by cationic stimulation results in the formation of poly-carbonates.13The dissolution of transition metal cations forms surface inactive Li x MO y phases.14Their precipitation on the anode side destroys the passivation of the negative electrodes.15Red-ox reactions with solution species form inactive LiMO y with the transition metal M at a lower oxidation state.14LiMO y compounds are spontaneously delithiated in air due to reactions with CO 2.16Acid–base reactions occur in the LiPF 6solutions (trace HF,water)that are commonly used in Li-ion batteries.Finally,LiCoO 2itself has a rich surface chemistry that inﬂuences its performance:4LiCo III O 2 !Co IV O 2þCo II Co III 2O 4þ2Li 2O !4HF4LiF þ2H 2O Co III compounds oxidize alkyl carbonates;CO 2is one of the products,Co III /Co II /Co 2+dissolution.14Interestingly,this process seems to be self-limiting,as the presence of Co 2+ions in solution itself stabilizes the LiCoO 2electrodes,17However,Co metal in turn appears to deposit on the negative electrodes,destroying their passivation.Hence the performance of many types of electrodes depends on their surface chemistry.Unfortunately surface studies provide more ambiguous results than bulk studies,therefore there are still many open questions related to the surface chemistry of Li-ion battery systems.It is for these reasons that proper R&D of advanced materials for Li-ion batteries has to include bulk structural and perfor-mance studies,electrode–solution interactions,and possible reﬂections between the anode and cathode.These studies require the use of the most advanced electrochemical,18structural (XRD,HR microscopy),spectroscopic and surface sensitive analytical techniques (SS NMR,19FTIR,20XPS,21Raman,22X-ray based spectroscopies 23).This presentation provides a review of the forefront of the study of advanced materials—electrolyte systems,current collectors,anode materials,and ﬁnally advanced cathodes materials used in Li-ion batteries,with the emphasis on contributions from the authors’group.ExperimentalMany of the materials reviewed were studied in this laboratory,therefore the experimental details have been provided as follows.The LiMO 2compounds studied were prepared via self-combus-tion reactions (SCRs).24Li[MnNiCo]O 2and Li 2MnO 3$Li/MnNiCo]O 2materials were produced in nano-andsubmicrometric particles both produced by SCR with different annealing stages (700 C for 1hour in air,900 C or 1000 C for 22hours in air,respectively).LiMn 1.5Ni 0.5O 4spinel particles were also synthesized using SCR.Li 4T 5O 12nanoparticles were obtained from NEI Inc.,USA.Graphitic material was obtained from Superior Graphite (USA),Timcal (Switzerland),and Conoco-Philips.LiMn 0.8Fe 0.2PO 4was obtained from HPL Switzerland.Standard electrolyte solutions (alkyl carbonates/LiPF 6),ready to use,were obtained from UBE,Japan.Ionic liquids were obtained from Merck KGaA (Germany and Toyo Gosie Ltd.,(Japan)).The surface chemistry of the various electrodes was charac-terized by the following techniques:Fourier transform infrared (FTIR)spectroscopy using a Magna 860Spectrometer from Nicolet Inc.,placed in a homemade glove box purged with H 2O and CO 2(Balson Inc.air puriﬁcation system)and carried out in diffuse reﬂectance mode;high-resolution transmission electron microscopy (HR-TEM)and scanning electron microscopy (SEM),using a JEOL-JEM-2011(200kV)and JEOL-JSM-7000F electron microscopes,respectively,both equipped with an energy dispersive X-ray microanalysis system from Oxford Inc.;X-ray photoelectron spectroscopy (XPS)using an HX Axis spectrom-eter from Kratos,Inc.(England)with monochromic Al K a (1486.6eV)X-ray beam radiation;solid state 7Li magic angle spinning (MAS)NMR performed at 194.34MHz on a Bruker Avance 500MHz spectrometer in 3.2mm rotors at spinning speeds of 18–22kHz;single pulse and rotor synchronized Hahn echo sequences were used,and the spectra were referenced to 1M LiCl at 0ppm;MicroRaman spectroscopy with a spectrometerfrom Jobin-Yvon Inc.,France.We also used M €ossbauer spec-troscopy for studying the stability of LiMPO 4compounds (conventional constant-acceleration spectrometer,room temperature,50mC:57Co:Rh source,the absorbers were put in Perspex holders.In situ AFM measurements were carried out using the system described in ref.25.The following electrochemical measurements were posite electrodes were prepared by spreading slurries comprising the active mass,carbon powder and poly-vinylidene diﬂuoride (PVdF)binder (ratio of 75%:15%:10%by weight,mixed into N -methyl pyrrolidone (NMP),and deposited onto aluminium foil current collectors,followed by drying in a vacuum oven.The average load was around 2.5mg active mass per cm 2.These electrodes were tested in two-electrode,coin-type cells (Model 2032from NRC Canada)with Li foil serving as the counter electrode,and various electrolyte puter-ized multi-channel battery analyzers from Maccor Inc.(USA)and Arbin Inc.were used for galvanostatic measurements (voltage vs.time/capacity,measured at constant currents).Results and discussionOur road map for materials developmentFig.1indicates a suggested road map for the direction of Li-ion research.The axes are voltage and capacity,and a variety of electrode materials are marked therein according to their respective values.As is clear,the main limiting factor is the cathode material (in voltage and capacity).The electrode mate-rials currently used in today’s practical batteries allow forD o w n l o a d e d b y B e i j i n g U n i v e r s i t y o f C h e m i c a l T e c h n o l o g y o n 24 F e b r u a r y 2011P u b l i s h e d o n 23 F e b r u a r y 2011 o n h t t p ://p u b s .r s c .o r g | d o i :10.1039/C 0J M 04225Ka nominal voltage of below 4V.The lower limit of the electro-chemical window of the currently used electrolyte solutions (alkyl carbonates/LiPF 6)is approximately 1.5V vs.Li 26(see later discussion about the passivation phenomena that allow for the operation of lower voltage electrodes,such as Li and Li–graphite).The anodic limit of the electrochemical window of the alkyl carbonate/LiPF 6solutions has not been speciﬁcally determined but practical accepted values are between 4.2and 5V vs.Li 26(see further discussion).With some systems which will be discussed later,meta-stability up to 4.9V can be achieved in these standard electrolyte solutions.Electrolyte solutionsThe anodic stability limits of electrolyte solutions for Li-ion batteries (and those of polar aprotic solutions in general)demand ongoing research in this subﬁeld as well.It is hard to deﬁne the onset of oxidation reactions of nonaqueous electrolyte solutions because these strongly depend on the level of purity,the presence of contaminants,and the types of electrodes used.Alkyl carbonates are still the solutions of choice with little competition (except by ionic liquids,as discussed below)because of the high oxidation state of their central carbon (+4).Within this class of compounds EC and DMC have the highest anodic stability,due to their small alkyl groups.An additional beneﬁt is that,as discussed above,all kinds of negative electrodes,Li,Li–graphite,Li–Si,etc.,develop excellent passivation in these solutions at low potentials.The potentiodynamic behavior of polar aprotic solutions based on alkyl carbonates and inert electrodes (Pt,glassy carbon,Au)shows an impressive anodic stability and an irreversible cathodic wave whose onset is $1.5vs.Li,which does not appear in consequent cycles due to passivation of the anode surface bythe SEI.The onset of these oxidation reactions is not well deﬁned (>4/5V vs.Li).An important discovery was the fact that in the presence of Li salts,EC,one of the most reactive alkyl carbonates (in terms of reduction),forms a variety of semi-organic Li-con-taining salts that serve as passivation agents on Li,Li–carbon,Li–Si,and inert metal electrodes polarized to low potentials.Fig.2and Scheme 1indicates the most signiﬁcant reduction schemes for EC,as elucidated through spectroscopic measure-ments (FTIR,XPS,NMR,Raman).27–29It is important to note (as reﬂected in Scheme 1)that the nature of the Li salts present greatly affects the electrode surface chemistry.When the pres-ence of the salt does not induce the formation of acidic species in solutions (e.g.,LiClO 4,LiN(SO 2CF 3)2),alkyl carbonates are reduced to ROCO 2Li and ROLi compounds,as presented in Fig. 2.In LiPF 6solutions acidic species are formed:LiPF 6decomposes thermally to LiF and PF 5.The latter moiety is a Lewis acid which further reacts with any protic contaminants (e.g.unavoidably present traces of water)to form HF.The presence of such acidic species in solution strongly affects the surface chemistry in two ways.One way is that PF 5interactswithFig.1The road map for R&D of new electrode materials,compared to today’s state-of-the-art.The y and x axes are voltage and speciﬁc capacity,respectively.Fig.2A schematic presentation of the CV behavior of inert (Pt)elec-trodes in various families of polar aprotic solvents with Li salts.26D o w n l o a d e d b y B e i j i n g U n i v e r s i t y o f C h e m i c a l T e c h n o l o g y o n 24 F e b r u a r y 2011P u b l i s h e d o n 23 F e b r u a r y 2011 o n h t t p ://p u b s .r s c .o r g | d o i :10.1039/C 0J M 04225Kthe carbonyl group and channels the reduction process of EC to form ethylene di-alkoxide species along with more complicated alkoxy compounds such as binary and tertiary ethers,rather than Li-ethylene dicarbonates (see schemes in Fig.2);the other way is that HF reacts with ROLi and ROCO 2Li to form ROH,ROCO 2H (which further decomposes to ROH and CO 2),and surface LiF.Other species formed from the reduction of EC are Li-oxalate and moieties with Li–C and C–F bonds (see Scheme 1).27–31Efforts have been made to enhance the formation of the passivation layer (on graphite electrodes in particular)in the presence of these solutions through the use of surface-active additives such as vinylene carbonate (VC)and lithium bi-oxalato borate (LiBOB).27At this point there are hundreds of publica-tions and patents on various passivating agents,particularly for graphite electrodes;their further discussion is beyond the scope of this paper.Readers may instead be referred to the excellent review by Xu 32on this subject.Ionic liquids (ILs)have excellent qualities that could render them very relevant for use in advanced Li-ion batteries,including high anodic stability,low volatility and low ﬂammability.Their main drawbacks are their high viscosities,problems in wetting particle pores in composite structures,and low ionic conductivity at low temperatures.Recent years have seen increasing efforts to test ILs as solvents or additives in Li-ion battery systems.33Fig.3shows the cyclic voltammetric response (Pt working electrodes)of imidazolium-,piperidinium-,and pyrrolidinium-based ILs with N(SO 2CF 3)2Àanions containing LiN(SO 2CF 3)2salt.34This ﬁgure reﬂects the very wide electrochemical window and impressive anodic stability (>5V)of piperidium-and pyr-rolidium-based ILs.Imidazolium-based IL solutions have a much lower cathodic stability than the above cyclic quaternary ammonium cation-based IL solutions,as demonstrated in Fig.3.The cyclic voltammograms of several common electrode mate-rials measured in IL-based solutions are also included in the ﬁgure.It is clearly demonstrated that the Li,Li–Si,LiCoO 2,andLiMn 1.5Ni 0.5O 4electrodes behave reversibly in piperidium-and pyrrolidium-based ILs with N(SO 2CF 3)2Àand LiN(SO 2CF 3)2salts.This ﬁgure demonstrates the main advantage of the above IL systems:namely,the wide electrochemical window with exceptionally high anodic stability.It was demonstrated that aluminium electrodes are fully passivated in solutions based on derivatives of pyrrolidium with a N(SO 2CF 3)2Àanion and LiN(SO 2CF 3)2.35Hence,in contrast to alkyl carbonate-based solutions in which LiN(SO 2CF 3)2has limited usefulness as a salt due to the poor passivation of aluminium in its solutions in the above IL-based systems,the use of N(SO 2CF 3)2Àas the anion doesn’t limit their anodic stability at all.In fact it was possible to demonstrate prototype graphite/LiMn 1.5Ni 0.5O 4and Li/L-iMn 1.5Ni 0.5O 4cells operating even at 60 C insolutionsScheme 1A reaction scheme for all possible reduction paths of EC that form passivating surface species (detected by FTIR,XPS,Raman,and SSNMR 28–31,49).Fig.3Steady-state CV response of a Pt electrode in three IL solutions,as indicated.(See structure formulae presented therein.)The CV presentations include insets of steady-state CVs of four electrodes,as indicated:Li,Li–Si,LiCoO 2,and LiMn 1.5Ni 0.5O 4.34D o w n l o a d e d b y B e i j i n g U n i v e r s i t y o f C h e m i c a l T e c h n o l o g y o n 24 F e b r u a r y 2011P u b l i s h e d o n 23 F e b r u a r y 2011 o n h t t p ://p u b s .r s c .o r g | d o i :10.1039/C 0J M 04225Kcomprising alkyl piperidium-N(SO2CF3)2as the IL solvent and Li(SO2CF3)2as the electrolyte.34Challenges remain in as far as the use of these IL-based solutions with graphite electrodes.22Fig.4shows the typical steady state of the CV of graphite electrodes in the IL without Li salts.The response in this graph reﬂects the reversible behavior of these electrodes which involves the insertion of the IL cations into the graphite lattice and their subsequent reduction at very low potentials.However when the IL contains Li salt,the nature of the reduction processes drastically changes.It was recently found that in the presence of Li ions the N(SO2CF3)2Àanion is reduced to insoluble ionic compounds such as LiF,LiCF3, LiSO2CF3,Li2S2O4etc.,which passivate graphite electrodes to different extents,depending on their morphology(Fig.4).22 Fig.4b shows a typical SEM image of a natural graphite(NG) particle with a schematic view of its edge planes.Fig.4c shows theﬁrst CVs of composite electrodes comprising NG particles in the Li(SO2CF3)2/IL solution.These voltammograms reﬂect an irreversible cathodic wave at theﬁrst cycle that belongs to the reduction and passivation processes and their highly reversible repeated Li insertion into the electrodes comprising NG. Reversible capacities close to the theoretical ones have been measured.Fig.4d and e reﬂect the structure and behavior of synthetic graphiteﬂakes.The edge planes of these particles are assumed to be much rougher than those of the NG particles,and so their passivation in the same IL solutions is not reached easily. Their voltammetric response reﬂects the co-insertion of the IL cations(peaks at0.5V vs.Li)together with Li insertion at the lower potentials(<0.3V vs.Li).Passivation of this type of graphite is obtained gradually upon repeated cycling(Fig.4e), and the steady-state capacity that can be obtained is much lower than the theoretical one(372mA h gÀ1).Hence it seems that using graphite particles with suitable morphologies can enable their highly reversible and stable operation in cyclic ammonium-based ILs.This would make it possible to operate high voltage Li-ion batteries even at elevated temperatures(e.g. 4.7–4.8V graphite/LiMn1.5Ni0.5O4cells).34 The main challenge in thisﬁeld is to demonstrate the reasonable performance of cells with IL-based electrolytes at high rates and low temperatures.To this end,the use of different blends of ILs may lead to future breakthroughs.Current collectorsThe current collectors used in Li-ion systems for the cathodes can also affect the anodic stability of the electrolyte solutions.Many common metals will dissolve in aprotic solutions in the potential ranges used with advanced cathode materials(up to5V vs.Li). Inert metals such as Pt and Au are also irrelevant due to cost considerations.Aluminium,however,is both abundantand Fig.4A collection of data related to the behavior of graphite electrodes in butyl,methyl piperidinium IL solutions.22(a)The behavior of natural graphite electrodes in pure IL without Li salt(steady-state CV is presented).(b)The schematic morphology and a SEM image of natural graphite(NG)ﬂakes.(c)The CV response(3ﬁrst consecutive cycles)of NG electrodes in IL/0.5lithium triﬂuoromethanesulfonimide(LiTFSI)solution.(d and e)Same as(b and c)but for synthetic graphiteﬂakes.DownloadedbyBeijingUniversityofChemicalTechnologyon24February211Publishedon23February211onhttp://pubs.rsc.org|doi:1.139/CJM4225Kcheap and functions very well as a current collector due to its excellent passivation properties which allow it a high anodic stability.The question remains as to what extent Al surfaces can maintain the stability required for advanced cathode materials (up to 5V vs.Li),especially at elevated temperatures.Fig.5presents the potentiodynamic response of Al electrodes in various EC–DMC solutions,considered the alkyl carbonate solvent mixture with the highest anodic stability,at 30and 60 C.37The inset to this picture shows several images in which it is demonstrated that Al surfaces are indeed active and develop unique morphologies in the various solutions due to their obvious anodic processes in solutions,some of which lead to their effective passivation.The electrolyte used has a critical impact on the anodic stability of the Al.In general,LiPF 6solutions demonstrate the highest stability even at elevated temperatures due to the formation of surface AlF 3and even Al(PF 6)3.Al CCs in EC–DMC/LiPF 6solutions provide the highest anodic stability possible for conventional electrode/solution systems.This was demonstrated for Li/LiMn 1.5Ni 0.5O 4spinel (4.8V)cells,even at 60 C.36This was also conﬁrmed using bare Al electrodes polarized up to 5V at 60 C;the anodic currents were seen to decay to negligible values due to passivation,mostly by surface AlF 3.37Passivation can also be reached in Li(SO 2CF 3),LiClO 4and LiBOB solutions (Fig.5).Above 4V (vs.Li),the formation of a successful passivation layer on Al CCs is highly dependent on the electrolyte formula used.The anodic stability of EC–DMC/LiPF 6solutions and Al current collectors may be further enhanced by the use of additives,but a review of additives in itself deserves an article of its own and for this readers are again referred to the review by Xu.32When discussing the topic of current collectors for Li ion battery electrodes,it is important to note the highly innovative work on (particularly anodic)current collectors by Taberna et al.on nano-architectured Cu CCs 47and Hu et al.who assembled CCs based on carbon nano-tubes for ﬂexible paper-like batteries,38both of whom demonstrated suberb rate capabilities.39AnodesThe anode section in Fig.1indicates four of the most promising groups of materials whose Li-ion chemistry is elaborated as follows:1.Carbonaceous materials/graphite:Li ++e À+C 6#LiC 62.Sn and Si-based alloys and composites:40,41Si(Sn)+x Li ++x e À#Li x Si(Sn),X max ¼4.4.3.Metal oxides (i.e.conversion reactions):nano-MO +2Li ++2e À#nano-MO +Li 2O(in a composite structure).424.Li x TiO y electrodes (most importantly,the Li 4Ti 5O 12spinel structure).43Li 4Ti 5O 12+x Li ++x e À#Li 4+x Ti 5O 12(where x is between 2and 3).Conversion reactions,while they demonstrate capacities much higher than that of graphite,are,practically speaking,not very well-suited for use as anodes in Li-ion batteries as they generally take place below the thermodynamic limit of most developed electrolyte solutions.42In addition,as the reactions require a nanostructuring of the materials,their stability at elevated temperatures will necessarily be an issue because of the higher reactivity (due to the 1000-fold increase in surface area).As per the published research on this topic,only a limited meta-stability has been demonstrated.Practically speaking,it does not seem likely that Li batteries comprising nano-MO anodes will ever reach the prolonged cycle life and stability required for EV applications.Tin and silicon behave similarly upon alloying with Li,with similar stoichiometries and >300%volume changes upon lith-iation,44but the latter remain more popular,as Si is much more abundant than Sn,and Li–Si electrodes indicate a 4-fold higher capacity.The main approaches for attaining a workable revers-ibility in the Si(Sn)–Li alloying reactions have been through the use of both nanoparticles (e.g.,a Si–C nanocomposites 45)and composite structures (Si/Sn–M1–M2inter-metalliccompounds 44),both of which can better accommodate these huge volume changes.The type of binder used in composite electrodes containing Si particles is very important.Extensive work has been conducted to determine suitable binders for these systems that can improve the stability and cycle life of composite silicon electrodes.46As the practical usage of these systems for EV applications is far from maturity,these electrodes are not dis-cussed in depth in this paper.However it is important to note that there have been several recent demonstrations of how silica wires and carpets of Si nano-rods can act as much improved anode materials for Li battery systems in that they can serveasFig.5The potentiodynamic behavior of Al electrodes (current density measured vs.E during linear potential scanning)in various solutions at 30and 60 C,as indicated.The inset shows SEM micrographs of passivated Al surfaces by the anodic polarization to 5V in the solutions indicated therein.37D o w n l o a d e d b y B e i j i n g U n i v e r s i t y o f C h e m i c a l T e c h n o l o g y o n 24 F e b r u a r y 2011P u b l i s h e d o n 23 F e b r u a r y 2011 o n h t t p ://p u b s .r s c .o r g | d o i :10.1039/C 0J M 04225K。

建筑防水涂料标准化现状分析与对策

标准实践建筑防水涂料标准化现状分析与对策研究■ 王光英1 李冠中2* 张国华1（1.青岛市产品质量检验研究院；2青岛大洋灯塔防水有限公司）摘要：中国房地产市场商业化的推进，推动了建筑涂料行业的快速发展。

许多颇具功能特色的防水涂料也不断涌现。

然而，与世界先进水平国家相比，我国建筑防水涂料标准体系还存在着标准与建筑应用脱节、耐久性指标不健全、标准体系不统一等问题。

本文对我国建筑防水涂料行业及标准化现状进行分析，提出防水涂料产品固有性能和应用性能的概念，结合建筑业需求，指出行业在标准化方面存在的问题与不足，并提出改进对策和建议。

关键词：防水涂料，标准化，应用性能，建筑，对策DOI编码：10.3969/j.issn.1002-5944.2022.22.019Analysis on the Current Situation and Countermeasures of Standardizationof Building Waterproof CoatingWANG Guang-ying1 LI Guan-zhong2* ZHANG Guo-hua1（1.Qingdao Product Quality Test Research Institute; 2. Qingdao Dayang Dengta Waterprooﬁ ng Co., Ltd.）Abstract: The commercialization of China's real estate market has promoted the rapid development of the architectural coatings industry. Many functional waterproof coatings are also emerging. However, compared with the world's advanced countries, the standards system of architectural waterproof coatings in China is not unified enough, and there are problems such as disconnection between standards and architectural applications, imperfect durability indicators, and inconsistent standards systems. This paper analyzes the current situation of construction waterproof coating industry and standardization in China, puts forward the concept of inherent performance and application performance of waterproof coating products, and points out the problems and deﬁ ciencies in the standardization of the industry in combination with the needs of the construction industry, and puts forward countermeasures and suggestions on improvement. Keywords: waterproof coating, standardization, application performance, construction, countermeasures1 引言近二十余年来建筑业的蓬勃发展，极大地促进了建筑材料的发展和进步。

SOLIDWORKS Composer 3D 技术文档说明书

OBIETTIVISOLIDWORKS® Composer è uno strumento 3D che consente di riutilizzare i dati tecnici 3D per creare contenuti grafici in grado di spiegare processi e procedure all'interno delle comunicazioni tecniche. Questi contenuti includono istruzioni di assemblaggio per la produzione, manuali dei prodotti, istruzioni di installazione, manuali di assistenza, manuali per la formazione, brochure di marketing e offerte per le vendite.PANORAMICASOLIDWORKS Composer è uno strumento per la crea-zione di supporti per la comunicazione, quali istruzioni di assemblaggio, elenchi di parti e supporti di presen-tazione, che possono essere costituiti da pagine HTML interattive, animazioni, immagini rasterizzate o grafica vettoriale. I dati di SOLIDWORKS o di altre applicazioni CAD possono essere importati in SOLIDWORKS Composer e organizzati in viste costituite da istantanee dei dati dell'assieme con orientamenti e stati diversi, in cui le parti vengono mostrate e nascoste in base alle esigenze. 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Per ulteriori informazioni, visitare il sito web /it .AmericheDassault Systèmes 175 Wyman Street Waltham, MA 02451 USAEuropa/Medio Oriente/Africa Dassault Systèmes10, rue Marcel Dassault CS 4050178946 Vélizy-Villacoublay Cedex FranciaDassault Systèmes Italia s.r.l.+39-049-8176400 ************************©2018 D a s s a u l t S y s t èm e s . T u t t i i d i r i t t i r i s e r v a t i . 3D E X P E R I E N C E , l 'i c o n a C o m p a s s , i l l o g o 3D S , C A T I A , S O L I D W O R K S , E N O V I A , D E L M I A , S I M U L I A , G E O V I A , E X A L E A D , 3D V I A , 3D S W Y M , B I O V I A , N E T V I B E S , I F W E e 3D E X C I T E s o n o m a r c h i c o m m e r c i a l i o m a r c h i r e g i s t r a t i d i D a s s a u l t S y s t èm e s , u n a "s o c i ét é e u r o p ée n n e " f r a n c e s e (r e g i s t r o d e l c o m m e r c i o d i V e r s a i l l e s n r . B 322 306 440), o d e l l e s u e c o n s o c i a t e n e g l i S t a t i U n i t i e /o i n a l t r i P a e s i . T u t t i g l i a l t r i m a r c h i s o n o d i p r o p r i e t à d e i r i s p e t t i v i p r o p r i e t a r i . L 'u s o d e i m a r c h i d i D a s s a u l t S y s t èm e s o d e l l e s u e c o n s o c i a t e è s o g g e t t o a l l a l o r o a p p r o v a z i o n e e s p l i c i t a p e r i s c r i t t o .FUNZIONALITÀSOLIDWORKS Composer• Le istruzioni di assemblaggio contengono informazioni aggiornate derivanti dagli ordini di modifica emantengono le informazioni di progettazione, riducendo i dubbi nell'officina e le incomprensioni dovute alle barriere linguistiche.• I manuali dei prodotti, le guide all'assistenza eall'installazione hanno sempre un aspetto professionale e vengono aggiornati a ogni modifica dei prodotti. 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Advanced materials research

aemail: yaoxue.0612@; b* email: lxg@; c email: hanbenchao@
Keywords: Konjac glucomannan; Poly(acrylic acid); Interpenetrating polymer network; Enzymatic degradation; Molecular weight
Introduction KGM is a high molecular weight water-soluble non-ionic polysaccharide found in tubers of
Amorphophallus konjac[1-2]. KGM with various molecular weights can show different physicochemical properties[3-4] and physiological function[5]. Polymer molecular weight has an influence on their efficacy in vitro and in vivo when they are used as the drug delivery systems. For example, polymeric nanoparticles based on low molecular weight (MW) chitosan exhibit higher transfection efficiency in vitro and in vivo than those made from high molecular weight chitosan[6].
β-mannanase and were hydrolyzed for different times. The enzymatic hydrolysis solution was precipitated with ethanol, and then the precipitate was dried at room temperature and ground into powders. Consequently, a series of powdered KGM with different molecular weights were obtained and were coded as KGM1, KGM2 and KGM3.

蚯蚓粪复合基质在蔬菜育苗上的应用

2022年7月热带农业科学第42卷第7期Jul. 2022 CHINESE JOURNAL OF TROPICAL AGRICULTURE Vol.42, No.7收稿日期 2022-02-22；修回日期 2022-03-24基金项目不同作物应用蚯蚓粪效果试验（基质配方）项目。

第一作者张珂（1988—），女，农艺师，研究方向为土壤改良与地力提升，E-mail ：****************。

通讯作者李光义（1983—），男，副研究员，研究方向为废弃物资源化利用，E-mail ：******************。

蚯蚓粪复合基质在蔬菜育苗上的应用张珂1 王朝弼1 王熊飞1 祁君凤1 刘存法1 李光义2（1. 海南省土壤肥料总站海南海口 571100；2. 中国热带农业科学院环境与植物保护研究所海南海口 571101）摘要利用蚯蚓粪和腐熟菌渣为替代草炭的主要原料，以商品基质为对照，筛选圣女果、辣椒及豇豆育苗基质配方，在最佳基质配方基础上对其进行理化性质及磷养分优化并验证育苗效果后，最终形成圣女果、辣椒及豇豆育苗基质最终配方。

研究结果表明：（1）基质配方S5（S0∶YF=40∶60，V /V ）对圣女果、辣椒及豇豆的育苗效果最好，圣女果幼苗和豇豆幼苗生长指标达到商品基质育苗水平，辣椒幼苗生长指标不如商品基质。

（2）基质优化配方S6（菌渣∶草炭∶珍珠岩∶蚓粪=35∶35∶20∶10（V /V ））所育圣女果幼苗和豇豆幼苗达到商品基质育苗水平，辣椒幼苗生长指标优于商品基质，壮苗指数较商品基质提高了43.9%。

（3）基质配方S6添加过磷酸钙2 g/L 所育圣女果生长指标最好，壮苗指数较商品基质提高了26.0%；基质配方S6添加过磷酸钙对辣椒幼苗指标的促进作用不明显；基质配方S6添加过磷酸钙3 g/L 所育豇豆幼苗生长指标最好。

因此，圣女果、辣椒和豇豆育苗基质配方分别为“菌渣∶草炭∶珍珠岩∶蚯蚓粪= 35∶35∶20∶10（V /V ）+2 g/L 过磷酸钙”“菌渣∶草炭∶珍珠岩∶蚯蚓粪=35∶35∶20∶10（V /V ）”和“菌渣∶草炭∶珍珠岩∶蚯蚓粪=35∶35∶20∶10（V /V ）+3 g/L 过磷酸钙”。

节能技术在炭黑生产过程中的应用

生产、日用品制作等方面占据着重要地位。

因为炭黑生产需要耗费大量能源与资源，所以做好其节能降耗工作尤为关键，同时亦是我国产业政策调整后提出的新要求，这样不但能够有利于企业能耗的减小，而且还能实现企业的降本增效。

但由于炭黑需求量的与日俱增，我国炭黑生产工业规模逐年扩大，甚至跃居世界第一，其生产过程中导致的能源消耗和环境污染问题日益严重，甚至达到触目惊心的地步。

由于炭黑生产所损耗的能源和资源绝大部分属于不可再生资源，尽管当前炭黑生产工艺技术有了很大创新，但油类原料利用率居高不下的现实问题还没到很好的改善。

而且部分炭黑生态企业没有开展工程能源预期管理，导致大量水资源的浪费。

相较于普通工业生产用水来说，炭黑生产过程中冷却系统的水供给量要大得多。

而且无法多次循环冷却水资源导致供给端口发生浪费，水资源损耗量要远远超出预期。

除此之外，部分炭黑生产企业缺乏保护环境的意识，生产观念没能及时更新，导致生产环节极易发生各类矛盾冲突。

例如，在生产炭黑产品时，在高温加热与分解原料油的过程中会有巨大热能的出现，无法快速被冷却环节吸收，而且也没能合理利用与评估余热，导致大部分情况都无法使用余热，导致热能浪费严重，并使得后期冷却用水量增多。

部分企业在以往检查炭黑生产能源消耗情况下，仅仅是对其生产过程有无根据相应规定流程来开展进行查验，而忽略了具体使用水资源的量以及燃油加热所产生的能源损耗，存在生产管理漏洞，制约着炭黑生产节能降耗工作的开展。

3 炭黑生产中节能技术应用分析3.1 急冷锅炉设备的应用在最初的炭黑生产步骤中，由于空气和油类物质接触燃烧后所产生一系列的高温裂解反应，使锅炉内温度达到近1 800 ℃。

而粗糙炭黑收集过程的解除限制需要大量喷水进行急速冷却，使锅炉内产生的黑色烟气降低温度，这个过程中喷0 引言随着我国社会经济的发展，对自然资源需求量也在不断增加，我国的炭黑生产工业由于在工艺流程、设备等方面的原因，在生产过程中对炭黑原料的如煤焦油、天然气等损耗较大，从而消耗大量能量，对环境产生污染并对生产经济效益造成不利影响。

两种不同的新型真空预压法在真空预压浅层预处理中的对比研究

随着沿海城市经济的快速发展，土地资源日益短缺，尤其是港口工程的建设，需要考虑到航道清淤和工期要求，出现了新吹填淤泥就亟需进行浅层预处理的场地，为后期深层处理提供作业面。

浅层预处理一般采用直排式真空预压技术，刘健等人依托工程项目，采用不同的管路布置方案或排水板间距分区的现场试验，并对其处理结果进行对比分析[1-2]。

袁保军等人结合某次填淤泥工程，进行了浅层预处理直排式真空预压的现场试验研究[3-5]。

杨茯苓、谢荣星对浅层处理的排水系统进行了研发，对比了不同方案的处理效果[6-7]。

王建华、蒋杰、何洪涛等在现场试验的基础上，总结了不同类型排水板、钢丝软管与蝶形接头直连和采用大泵的优点，结合监测和检测数据分析了处理效果[8-10]。

两种不同的新型真空预压法在真空预压浅层预处理中的对比研究龚大利（中国石油天然气股份有限公司天然气销售分公司）摘要：随着沿海地区经济的快速发展，围海造陆已成为解决用地紧缺的优选方式，吹填土的地基处理一般采用真空预压法，传统真空预压法具有耗能高、施工不方便和质量控制难等缺点。

在科技、理论和工程实践不断发展的基础上，针对传统真空预压法出现的问题提出了新的抽真空设备和施工工艺，并在较多项目得到了成功应用。

基于现场实际项目，对比分析了不同新型抽真空设备的处理效果，均能满足设计要求，同时对两种不同设备的能效进行对比分析，提出真空预压处理面积在80000m 2以上时采用大泵集成系统较好，反之采用真空小泵设备，可最大限度的节省电能，为类似工程的设计和施工提供相关经验。

关键词：真空预压；新型设备；能效对比；地表沉降；经验公式DOI :10.3969/j.issn.2095-1493.2023.03.006Contrastive research on two different new vacuum pre-pressure methods in the shal⁃low pretreatment of vacuum pre-pressure GONG DaliNatural Gas Sales Company，CNPCAbstract：With the rapid economic development of coastal areas,sea reclamation has become the pre-ferred way to solve the shortage of land．The vacuum pre-pressure method is generally used for the foundation treatment of blown-in soils．The traditional vacuum pre-pressure method has the disad-vantages including high energy consumption，inconvenient construction and difficult quality control ．Based on the continuous development of technology，theory and engineering practice，with the prob-lems arising from the traditional vacuum pre-pressure method，new evacuation equipment and con-struction techniques have been proposed and successfully applied in more projects．Based on actual projects on site，the treatment effects of different new vacuum equipment are compared and analyzed and all meet the design requirements．At the same time，the energy efficiency of two different equip-ment is compared and analyzed，proposing that the use of integrated system with a large pump should be used when the treatment area of vacuum pre-pressure is greater than 80000m 2．On the contrary，the use of small vacuum pumps can can maximize the savings of electricity，which provides relative ex-perience for the design and construction of similar projects ．Keywords：vacuum pre-pressure；new type equipment；energy efficiency comparison；surface settle-ment；empirical formula作者简介：龚大利，高级工程师，2010年博士毕业于东北石油大学（油气储运工程），从事油气储运设施建设项目管理和创新研究工作，139****3212，*****************，北京市朝阳区安立路101号院-3号名人大厦，100101。

分子蒸馏技术在天然产物分离纯化中应用进展

分子蒸馏技术在天然产物分离纯化中应用进展李　燕1，2，刘军海2（1. 聊城大学农学院，　山东聊城　252059； 2. 聊城大学化工学院，　山东聊城　252059）摘　要：分子蒸馏技术是一种新型分离技术，具有真空度高、操作温度低和物料受热时间短等独特优点，在天然产物分离与提纯方面有着重要应用。

该文对分子蒸馏技术在天然产物分离与纯化中应用进展进行综述。

关键词：分子蒸馏；天然产物；分离纯化Application progress on molecular distillation in isolation andpurification for crude substanceLI Yan 1，2，LIU Jun-hai 2（1. College of Agronomy，Liaocheng University，Liaocheng 252059，China；2. College of Chemistry and Chemical Engineering，Liaocheng University，Liaocheng，252059，China）Abstract：Molecular distillation is a new isolation technique. Owing to the characteristic of highvacuum degree，low distillation temperature and short time being hot，this technique can wonderfully ensure the natrural quality of the substance and is widely used in the distillation，condensation and isolation of crude substance. Recent application progress of molecular distillation on isolation and purification in crude subatance was reviewed briefly in this paper.Key words：molecular distillation；crude substance；isolation and purification 中图分类号：TQ028.3＋1文献标识码：A文章编号：1008―9578（2011）03―0007―05收稿日期：2011–01–30作者简介：李燕（1980~ ），女，讲师，硕士研究生，研究方向：天然产物提取与分离。

2011年奥特奇亚太巡回演讲会

2011年奥特奇亚太巡回演讲会（广州站）成功落幕∙点击次数：81∙日期：2011-11-16 12:17∙编辑：admin∙来源：广东养猪信息网广东养猪信息网11月16日讯2011年度的奥特奇亚太地区巡回演讲在9月27日从新西兰的奥克兰启程,自11月7日将开始在环太平洋地区和东南亚地区举行。

11月15日上午，奥特奇中国区广州站的演讲会在广州白云万达希尔顿国际酒店二楼的白云会议厅成功落下帷幕。

包括广东温氏食品有限公司技术中心﹑广西南宁富凤农牧有限公司等各饲料企业配方师﹑养殖公司负责人﹑养殖户﹑华南农业大学畜牧兽医专业在校学生﹑业内媒体如广东养猪信息网﹑南方农村报﹑中国水产前沿﹑广东饲料行业信息网等共100多人参加了奥特奇此站演讲会。

奥特奇方面演讲嘉宾阵容也很强大，Matthew Smith，Andreas Kocher博士，Paulo Rigolin，Alison Leary博士和Richard Murphy博士皆参与其中。

几位演讲嘉宾分别在动物营养﹑动物遗传和市场营销方面有较深的造诣。

奥特奇中国南方区总经理卢克伦也出席了本站演讲会。

演讲会上，嘉宾们分别作了《动物生产性能和养殖利润的行业变革法则》﹑《应对当今和未来挑战的实用性解决方案》等报告。

奥特奇是全球知名的动保企业，总部位于美国肯塔基州莱克星顿。

奥特奇在美国总部、爱尔兰和泰国分别建立了生物研究中心。

目前已在全球119个国家设立办事机构，在全球范围内拥有14个生产基地。

奥特奇以“ 行业变革者”身份活跃在全球动物保健产业，致力于帮助业界人士辨明农业行业变革的关键时间点,改变现有社交方式, 克服目前农业产业所面临的挑战。

演讲会上Paulo Rigolin博士提出，目前包括中国在内世界各国都基本出现粮食产量赶不上需求的增长的状况，粮食开始变得短缺。

畜牧业的发展也将遇到动物饲料原料短缺的瓶颈。

中国已经从玉米出口国变成玉米进口国了。

那么该如何解决畜牧业发展跟饲粮短缺的矛盾？奥特奇给出了解决方案：运用固态发酵技术从海藻﹑纤维中提取更多的能量，Alison Leary博士论述了奥特奇的“程控营养”理念。

First-principles study of the structural, vibrational, phonon and thermodynamic

1. Introduction Ultra-high temperature ceramics (UHTCs) with melting temperatures in excess of 3000 K are usually composed by the refractory borides, carbides and nitrides of early transition metals [1–7]. Among the UHTCs, transition metal carbides (TMC) such as TiC, ZrC and HfC are metallic compounds with unique physical and chemical properties including an extremely high melting point and hardness, chemical stability, corrosion resistance combined with metallic electrical and thermal conductivities [5–10]. These features give transition metal carbides the capability to withstand high temperatures in oxidizing environments, making them candidates for applications in the atmosphere of extreme thermal and chemical environments [6,7]. The structural, vibrational, phonon and thermodynamic properties of IVb group transition metal carbides have been investigated experimentally [10–17] and theoretically [13,18–28] in the earlier reports. In the 1970s, the phonon dispersion relations of TiC, ZrC and HfC were measured using inelastic neutron scattering by Pintschovius et al. [10] and Smith et al. [15–17]. Lattice dynamics calculation and the phonon dispersion relations of transition metal carbides such as ZrC and HfC were reported using a phenomenological ‘‘double-shell’’ model theory [18] where long-range interatomic interactions were taken into account in order to get a

MANUFACTURE PARAMETERS GROUPING AND ANALYZING METH

专利名称：MANUFACTURE PARAMETERS GROUPING AND ANALYZING METHOD, ANDMANUFACTURE PARAMETERS GROUPINGAND ANALYZING SYSTEM发明人：Li-Chin Wang,Ya-Ching Cheng,Chien-Hung Chen,Chun-Liang Hou,Da-Ching Liao申请号：US15820662申请日：20171122公开号：US20190087481A1公开日：20190321专利内容由知识产权出版社提供专利附图：摘要：A manufacture parameters grouping and analyzing method, and a manufacture parameters grouping and analyzing system are provided. The manufacture parameters grouping and analyzing method includes the following steps: A plurality of process factors are classified into a plurality of groups. In each of the groups, an intervening relationship between any two of the process factors is larger than a predetermined correlation value. In each of the groups, at least one representative factor is selected from each of the groups according to a plurality of outputting relationships of the process factors related to an output factor or a plurality of sample amounts of the process factors. Finally, the representative factor is used for various applications.申请人：UNITED MICROELECTRONICS CORP.地址：Hsinchu TW国籍：TW更多信息请下载全文后查看。

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关键词：量功能展开（Ｄ）；质量工具；质量信息；集成的ＱＦ系统（ＱＦ）质ＱＦＤＩＤＳ中图分类号：２３２Ｆ７．文献标识码：Ａ
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光伏产业人才引培现状及对策建议

河南科技Henan Science and Technology 科技管理总779期第九期2022年5月光伏产业人才引培现状及对策建议乔路1王佳音2（1.中国信息通信研究院，北京100191；2.中国软件评测中心，北京100081）摘要：光伏产业是半导体技术与电力技术结合发展的战略性新兴产业，产业发展对调整能源结构、推进能源生产和消费革命、实现“碳达峰、碳中和”（双碳）战略具有重要意义，需要高端化、专业化、复合型、梯队化的人才队伍支撑。

当前我国光伏产业迎来市场化建设高峰，在能源转型和产业快速发展的双轮驱动下，企业自造血能力不足、人才流动性过大、供需错配、产教脱节、人才体系建设不完善等问题成为我国光伏产业提速升级和高质量发展的掣肘。

笔者分析了我国光伏产业人才存在的问题和原因，针对我国光伏产业人才引培困境提出对策建议。

关键词：光伏；人才；供需；碳达峰；碳中和中图分类号：G642文献标志码：A文章编号：1003-5168（2022）9-0155-04 DOI:10.19968/ki.hnkj.1003-5168.2022.09.035Present Situation and Countermeasures of Talent Introduction andTraining in Photovoltaic IndustryQIAO Lu1WANG Jiayin2(1.China Academy of Information and Communications Technology,Beijing100191,China;2.China SoftwareTesting Center,Beijing100081,China)Abstract:Photovoltaic(PV)industry is a strategic emerging industry that combines semiconductor tech⁃nology and power technology.Industrial development is of great significance to adjusting the energy structure,promoting the revolution of energy production and consumption,and realizing the"emission peak,carbon neutrality"strategy.To achieve the goal,a talent team,which is high-end,professional, compound and echeloned,is highly demanded.At present,the PV industry of China is ushering in the peak of marketization construction.However,the PV industry still has many problems in talent team that constraints the accelerating,upgrading and high-quality development of the industry,such as insuffi⁃cient self-hematopoietic capacity,excessive talent mobility,mismatch of supply and demand,disconnec⁃tion between industry and education,imperfect talent system construction and so on.The author analyzed the problems and causes of talents in our PV industry,put forward suggestions for solving the dilemma of the PV industry talents.Keywords:PV industry;talent;supply and demand;emission peak;carbon neutrality1“双碳”时代光伏产业人才发展新需求我国光伏产业虽仅有几十年的发展历程，但已成长为支柱型新能源产业之一，并形成较为成熟的产业链、供应链和价值链。

【全文】英语演讲之人物介绍ppt课件

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Jean - Pierre - Louise sauvage as early as in 1983 made the first step of molecular machines. He was successfully connect ring molecules into chain, called hydrocarbon. Molecules, generally speaking, there are strong covalent bond together, the atoms in a covalent bond share electrons, but in the chain molecules are more liberal machine link together. Can a machine can perform tasks must contain relatively moving parts. The two interlocked rings just in this condition is satolm at noon local time 5, 2016 Nobel Prize in chemistry in the royal Swedish academy of sciences, jean - Pierre - Louise sauvage, j. Fraser stoddart jazz and Bernard - L - fehling plus three scientists to share the prize, for their study in terms of "synthetic molecular machines".

防喷器远程控制装置自卸压四位四通转阀的研究与设计

文章编号：1000 − 7393(2022)06 − 0706 − 05 DOI: 10.13639/j.odpt.2022.06.007防喷器远程控制装置自卸压四位四通转阀的研究与设计李正军盖靖安中国石油集团西部钻探工程有限公司引用格式：李正军，盖靖安. 防喷器远程控制装置自卸压四位四通转阀的研究与设计［J ］. 石油钻采工艺，2022，44（6）：706-710.摘要：在维修更换防喷器闸板、胶芯等作业前必须对防喷器关闭腔和开启腔卸压，而传统三位四通转阀存在操作复杂、压力浪费、各阀件磨损、管汇卸压后所有控制对象均无法远程操作的问题，为此，设计了自卸压四位四通转阀。

在原有阀体及阀芯内部分别新增一条卸压油道，并将其改造成自卸压四位四通转阀，实际操作时只需将该转阀手柄扳至卸压位，便既能保留管汇压力，又可对维修作业对象进行独立卸压，卸压后仍可远程液压控制除维修对象外的其他控制对象，使得维修和更换防喷器闸板、胶芯等作业过程更加低耗、简单高效。

该设计降低了各阀件长期开关造成磨损，大幅度提升了作业效率。

关键词：防喷器；远程控制室；自卸压；四位四通转阀；井控中图分类号：TE921.5 文献标识码： AResearch and design of four-position four-way rotary valve with automated pressure relief forblowout preventer remote control devicesLI Zhengjun, GAI Jing’anCNPC Xibu Drilling Engineering Co., Ltd., Urumchi 830013, Xinjiang , ChinaCitation: LI Zhengjun, GAI Jing’an. Research and design of four-position four-way rotary valve with automated pressure relief for blowout preventer remote control devices ［J ］. Oil Drilling & Production Technology, 2022, 44(6): 706-710.Abstract: It is required to unload the closing and opening chambers of blowout preventers before repairing or replacing the rams and rubber seals of blowout preventers. The conventional three-position four-way rotary valve suffers from complex operation, waste of pressure, wear of valves and the disadvantage that all controlled components cannot be remotely operated after pressure relief of pipes. Given this, the four-position four-way rotary valve was developed. An extra oil unloading path was designed for the valve body and element, respectively to change the original valve into a four-position four-way rotary valve capable of automated pressure relief.In practice, it is required to only switch the valve handle to the unloading position to separately depressurize the repair target while maintaining the pressure in the rest pipes. All the other controlled components, except for those to be repaired, are under remote hydraulic control. The invention simplifies operations of repairing and replacing blowout preventer rams and rubber seals, reduces their energy consumption and improves their efficiency. The presented design also decreases the wear of valves attributed to repeated switching and greatly enhances operational efficiency.Key words: blowout preventer; remote control console; automated pressure relief; four-position four-way rotary valve; well control第一作者: 李正军(1988-)，2011年毕业于中国石油大学(华东)石油工程专业，现从事钻井工程技术研究与管理工作。

CIRCUIT TECHNIQUES FOR LOW

外文资料翻译资料来源文章名：CIRCUIT TECHNIQUES FOR LOW-VOLTAGEAND HIGH-SPEED A/D CONVERTERS书刊名：《Circuit Techniques for Low-Voltage and High-Speed A/D Converters》作者：Mikko E. Waltari, Kari A. I. Halonen出版社：Springer，2002章节：No. 4-7页码：pp. 33-40文章译名：峰值检测系统姓名：胡梅梅学号：1002150307指导教师(职称)：副教授专业：自动化班级：03班所在学院：武汉工程大学邮电与信息工程学院CIRCUIT TECHNIQUES FOR LOW-VOLTAGEAND HIGH-SPEED A/D CONVERTERSAbstractThe increasing digitalization in all spheres of electronics applications, from telecommunications systems to consumer electronics appliances, requires analog-to-digital converters (ADC) with a higher sampling rate, higher resolution, and lower power consumption. The evolution of integrated circuit technologies partially helps in meeting these requirements by providing faster devices and allowing for the realization of more complex functions in a given silicon area, but simultaneously it brings new challenges, the most important of which is the decreasing supply voltage.Based on the switched capacitor (SC) technique, the pipelined architecture has most successfully exploited the features of CMOS technology in realizing high-speedhigh-resolution ADC. An analysis of the effects of the supply voltage and technology scaling on SC circuits is carried out, and it shows that beneﬁts can be expected at least for the next few technology generations. The operational amplifier is a central building block in SC circuits, and thus a comparison of the topologies and their low voltage capabilities is presented.It is well-known that the SC technique in its standard form is not suitable for very low supply voltages, mainly because of insufficient switch control voltage. Two low-voltage modiﬁcations are investigated: switch bootstrapping and the switched opamp (SO) technique. Improved circuit structures are proposed for both. Two ADC prototypes using the SO technique are presented, while bootstrapped switches are utilized in three other prototypes.An integral part of an ADC is the front-end sample-and-hold (S/H) circuit. At high signalfrequencies its linearity is predominantly determined by the switches utilized. A review of S/H architectures is presented, and switch linearization by means of boot- strapping is studied and applied to two of the prototypes. Another important parameter is sampling clock jitter, which is analyzed and then minimized with carefully-designed clock generation and buffering.The throughput of ADCs can be increased by using parallelism. This is demonstrated on the circuit level with the double-sampling technique, which is applied to S/H circuits and a pipelined ADC. An analysis of nonidealities in double-sampling is presented. At the system level parallelism is utilized in a time-interleaved ADC. The mismatch of parallel signal paths produces errors, for the elimination of which a timing skew insensitive sampling circuit and a digital offset calibration are developed. A total of seven prototypes are presented: two double-sampled S/H circuits, a time-interleaved ADC, an IF-sampling self-calibrated pipelined ADC, a current steering DAC with a deglitcher, and two pipelined ADCs employing the SO technique.*Keywords:analog integrated circuit, analog-to-digital conversion, BiCMOS, boot- strapped switch, CMOS, double-sampling, IF-sampling, low voltage, operational ampliﬁer, pipelined analog-to-digital converter, sample-and-hold circuit, switched-capacitor, switched-opamp, time interleaving.IntroductionFor four decades the evolution of integrated circuits has followed Moore’s law, ac- cording to which the number of transistors per square millimeter of silicon doubles every 18 months. At the same time transistors have become faster, making possible ever-increasing clock rates in digital circuits. This trend seems set to continue for at least another decade without slowing down. Thus, in the near future the processing power of digital circuits willcontinue to increase at an accelerating pace.For analog circuits the evolution of technology is not as beneficial. Thus, there is a trend to move signal processing functions from the analog domain to the digital one, which, besides allowing for a higher level of accuracy, provides savings in power consumption and silicon area, increases robustness, speeds up the design pro- cess, brings flexibility and programmability, and increases the possibilities for design reuse. In many applications the input and output signals of the system are inherently analog, preventing all-digital realizations; at the very least a conversion between analog and digital is needed at the interfaces. Typically, moving the analog-digital boundary closer to the outside world increases the bit rate across it.In telecommunications systems the trend to boost bit rates is based on employing wider bandwidths and a higher signal-to-noise ratio. At the same time radio architectures in many applications are evolving toward software-deﬁned radio, one of the main characteristics of which is the shifting of the analog-digital boundary closer to the antenna.Because of these trends, there is an urgent need for data converters with increasing conversion rates and resolution. A part of this needed performance upgrade comes with the evolution technology, but often the demand is higher than this alone can provide. Thus, there is still room, and a need, for innovations in circuit design.The increasing integration level leads to systems with a smaller number of chips, the ultimate goal being a single chip solution, the system on a chip (SoC). This means that analog and digital circuits have to live on the same silicon die, which brings additional challenges in analog design, such as mixed signal issues and limitations in the choice of technology. Data converters are inherently mixed signal circuits and face the same challenges on a smaller scale even without going as far as SoC. Furthermore, the evolution of technology has been driven by the microprocessor industry and hence does not always go in the best direction for the analog. However, the recent rapid growth of the wireless telecommunications devices markethas given a boost to the development of advanced mixed signal technologies, such as silicon germanium-based BiCMOS.The main challenges in data converter design are decreasing supply voltage, short channel effects in MOS devices, mixed signal issues, the development of design and simulation tools, and testability. In analog-to-digital converters (ADCs), they need to be met at the same time as the requirements for sampling linearity, conversion rate, resolution, and power consumption are becoming tighter.This work concentrates on low voltage issues in ADCs by searching for and developing techniques and circuit structures suitable for today’s and the future’s low voltage technologies. In parallel, the increasing demands for ADCs have been answered by developing high-frequency high-linearity sampling techniques and applying them to ADC prototypes.A/D Converters*1 A/D ConversionAnalog-to-digital (A/D) conversion can be separated into two distinct operations: sampling and quantization. Sampling transforms a continuous time signal into a corresponding discrete time signal, while quantization converts continuous amplitude distribution into a set of discrete levels, which can be expressed with digital code words.Some A/D converter (ADC) architectures, the ﬂash for instance, can perform sampling and quantization simultaneously, and in some ADCs, which are targeted for DC signals, no sampling is needed at all. In high performance ADCs, however, sampling and quantization are usually separated to make it possible to optimize the circuitry for both tasks without compromises. Furthermore, the performance of many ADC architectures, which do not necessarily need a separate sampling circuit, can often be improved by adding one.The sampling operation has already been discussed in Chapter 3 and the architectures ofS/H circuits will be investigated in Chapter 5. In the remainder of this chapter the quantization operation is studied in more detail and the most common high-speed ADC architectures are introduced. There is also a bias is toward those architectures most suitable for CMOS technologies. Furthermore, the focus is on high-speed and medium- to high-resolution (8 bits or more) ADCs. Oversampling ADCs are not discussed.*2 Flash ADCFlash ADC, which is the fastest and one of the simplest ADC architectures, is shown in Figure 4.4. It performs 2N− 1 -level quantization with an equal number of comparators. The reference voltages for the comparators are generated using a resistor ladder, which is connected between the positive (V REF+) and the negative (V REF−) reference voltage determining the full-scale signal range. Together the comparator outputs form a 2N− 1 -bit code, where all the bits below the comparator whose reference is the ﬁrst to exceed the signal value are ones, while the bits above are all zeros. This so-called thermometer code is converted to N-bit binary word with a logic circuit, which can also contain functions for removing bit errors (bubbles).Since the input signal is directly connected to the inputs of the comparators, ﬂash architecture is very fast; the speed is only limited by the comparators. Thus, the fastest reported ADCs are realized with this architecture. Flash ADC also has very low latency—typically one to two clock cycles—which allows it to be utilized in applications using feedback (e.g. gain control loop).The most prominent drawback of ﬂash ADC is the fact that the number of comparators grows exponentially with the number of bits. Increasing the quantity of the comparators also increases the area of the circuit, as well as the power consumption. Thus, very high resolution ﬂash ADCs are not practical; typical resolutions are seven bits or below.Other issues limiting the resolution and speed include nonlinear input capacitance,location-dependent reference node time constants, incoherent timing of comparators laid out over a large area, and comparator offsets. To manage the offsets the utilization of auto-zeroing comparators is often necessary. Alternatively, the offsets and input capacitance can be reduced by means of distributed preamplification combined with averaging [45, 46], and possibly also with interpolation [47], which can both be considered as exponents of the signal preprocessing discussed in the previous section.In averaging each comparator is preceded by a preampliﬁer, whose output is coupled to the outputs of the adjacent preampliﬁers via a resistive averaging network. As a result, thein put signal for a comparator is not produced by its own preampliﬁer alone, but it is a weighted average of the outputs of the preampliﬁers in a small neighborhood. Comparator offset is reduced by the preampliﬁer gain and the preampliﬁer offset is an average of the random offsets of all the ampliﬁers participating in the amplification.Not every comparator needs to have a preampliﬁer of its own; instead, some (typically every other or three out of four) ampliﬁers can be eliminated and the missing signals generated by means of interpolation. Neither averaging nor interpolation reduces the number of the comparators, and thus it does not signiﬁca n tly extend ﬂash architecture toward higher resolutions.Recently, the main application of ﬂash ADCs has been in disk d rive read channel circuits and local area network interfaces. Typically, six-bit resolution with a sampling rate of several hundred megahertz is required. Even gigahertz rates seem to be within the reach ofstate-of-the-art CMOS technologies [48, 49].*3 Limitations and ImprovementsA well-known problem in this architecture is the fact that because of the folding the frequencies of the internal signals are much higher than the frequency of the incoming signal. As a result the performance typically begins to degrade at relatively low signal frequencies.The problem can be alleviated by using an S/H circuit in front of the converter, which, however, often diminishes the speed advantage. In distributed track-and-hold [54] each differential pair in the folding ampliﬁer has its own preampliﬁer with track-and-hold, which has less stringent specifications than a front-end S/H circuit would have. As a result, a higher speed can be achieved.The folding-and-interpolating architecture was originally developed for bipolar technology, which is ideal for realizing accurate open-loop circuits thanks to good V BE matching and high transconductance of the bipolar transistor. On the other hand, the offset voltages in MOS transistors are the main obstacle to increasing resolution. Thus, techniques such as averaging [46, 55] and self calibration [56] are used to reduce offset sensitivity.The folding can be carried out in many cascaded stages, minimizing the number of folds per stage [46, 55]. Consequently, the number of differential pairs connected to the input is reduced, which allows for the biasing of the transistors to a larger gate-source voltage, which increases the speed via increased transconductance. The capacitive load is also reduced, giving an additional increase in circuit speed.The throughput of the folding-and-interpolating architecture can be improved, at the cost of latency, by using pipelining, which can be realized by combining cascaded folding with the distributed T/H as demonstrated in [57] and [56]. Both of these designs also use subranging to reduce the number of folders.The resolution of the folding-and-interpolating ADCs reported has typically been in the 8–10-bit region and the sampling rates from some dozens of megahertz to a hundred megahertz. As high as a 400-MS/s sampling rate has been achieved [58]— with 6-bit resolution, though. The resolution of CMOS realizations has been limited to 10 bits, with one exception [56], which uses background self-calibration to cancel the offsets of the folding ampliﬁers.The folding ampliﬁer structure based on differential pairs does not allow for very*low-voltage operation, since it requires at least V T+ 2Vdsat on top of the input signal swing. Consequently, many of the ADCs described in the references use a 5-volt supply and not a single one goes below three volts.Operational AmpliﬁersThe opamp is a widely used building block in many types of analog circuits. Often, it is just the spot where the limits of the technology are first met, when trying to enhance the speed or reduce the power consumption of the circuits. In the SC technique and in the pipelined ADC based on it the opamp is a central component.Opamp design methodology and various circuit topologies have been thoroughly covered in many textbooks. Thus, presenting a comprehensive study in this context does not serve the present purpose; indeed it may not even be possible. Instead, this chapter tries to concentrate on issues related to low-voltage and high-speed design with modern IC technologies. The requirements of opamps in SC circuits are reviewed and the most important and suitable circuit topologies, with their pros and cons, are compared.*1 Output ImpedanceAnother characteristic feature of SC circuits is the load at the opamp output, which is typically purely capacitive. As a result, since there is no need to drive resistive loads, the opamp output impedance can be high, making it possible to use operational transconductance amplifiers (OTAs). The output stage of an OTA provides significant voltage gain, enabling the achieving of the gain target with a smaller number of stages.*2 Output Voltage RangeThe opamp output voltage range, as already discussed in Chapter 2, has a major impact on the signal-to-noise ratio. Consequently, maximizing the voltage swing is especially important in low-voltage and high resolution applications. Unfortunately, an output stage withhigh signal swing cannot usually provide very high output impedance, thus increasing the number of opamp stages. High output swing may also increase noise, since the output stage current sources cannot be optimally sized for low noise.In fully differential opamps the common mode voltage level at the output is not automatically determined. To set it to the wanted level (typically in the middle of the supply voltages) a common mode feedback (CMFB) circuit has to be used.*3 Input Common Mode RangeSC circuits typically employ opamps in the inverting feedback configuration (and are fully differential, making signal inversion possible simply by crossing the wires), which does not require a large common mode voltage range in the opamp input. Thus, low-voltage circuits can be constructed with opamps that do not have a rail-to-rail input stage. If present, the single-ended to differential conversion in the circuit front- end, however, may need an opamp in the non-inverting configuration. In addition, a fully differential input signal without an exactly-known common mode level requires some common mode input range from the opamp of the front-end stage to accommo- date signal CM voltage uncertainty or changes in it.In SC circuits the opamp input common mode level need not be equal to the out- put CM level, which is usually set to V DD/2 so as to maximize signal swing. This freedom can be utilized in low voltage circuits, for example when an nMOS input pair is employed, by setting the CM level close to the V DD, which leaves more voltage headroom for the input pair and the tail current source. In principle, the CM level can be raised all the way to V DD, but then care must be taken that the junction diodes of the pMOS switches attached to the opamp input do not become forward biased during the settling.ConclusionsTechnology scaling will bring advantages to SC circuits for the next few technology generations, but after that the effect of the decreasing supply voltage on the signal- to-noiseratio will start to dominate over the positive effects of shrinking transistor dimensions. Even before that, maximizing the signal range is essential for exploiting the beneﬁts of technology scaling. The signal range has the largest effect on the opamps, making the use of a rail-to-rail output stage mandatory. The switches do not have major difficulties in adapting to the nominal supply voltage of the technology. On the contrary, when a smaller-than-nominal supply voltage is used or a performance increase is pursued, techniques such as gate voltage bootstrapping or the switched-opamp technique are needed to guarantee a small enough switch on-resistance.In this work the utilization of the switched-opamp technique in pipelined ADCs has been demonstrated. Connecting the SO circuit to the outside world has been solved with a passive input interface circuit. The main limitation of the SO technique is the low speed caused by opamp switching and the decreased feedback factor. Thus, probably a better approach for low-voltage circuits requiring high speed is the selective use of bootstrapped switches and the utilization of different common mode signal levels at the opamp input and the output. The applications of the SO technique are in the areas where speed is not the most critical parameter.In wide-band radio receivers, moving the signal digitization into a high intermediate frequency is attractive. It has been demonstrated that the sampling can be done with relatively high linearity by using bootstrapped switches. A more fundamental problem is jitter, which can be alleviated only by extensive oversampling.The elimination of the bulk effect and signal-dependent drain and source junction capacitances is essential in a highly linear bootstrapped switch. This can most easily be accomplished with a triple-well process. The same, although with a smaller linearity boost, has here been demonstrated with a standard CMOS technology. Time interleaving is a way to extend the conversion rates of ADCs beyond the technology-determined limits of onestand-alone A/D channel. For eliminating the non-uniform sampling effects caused by timing skew between the parallel channels, a front-end S/H circuit is practically mandatory. As a result, it becomes a speed bottle- neck, typically limiting the number of parallel channels to a maximum of four.Moore’s law can be most effectively exploited by doing things digitally. This can be realized on the system level by moving analog functions into the digital domain, but also inside the analog system blocks by using even extensive amounts of digital circuitry to correct and compensate for the imperfections of the analog circuitry. In ADCs this means incorporating logic and memory for calibrating and correcting the offsets and the component mismatch.。

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